Protective device for electric circuits



Nov. 18, 1930. H. w. BAUMER PROTECTIVE DEVICE FOR ELECTRIC CIRCUITSFiled June 13 1925 2 Sheets-Sheet .,l

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Nov. 18, 1930. H. w. BAUMER 1,782,089

PROTECTIVE DEVICE FOR ELECTRIC CIRCUITS Filed June 13; 1925 2Sheets-Sheet 2 mmmwm ll/A a v 30 5f 6.

Patented Nov. 18, 1930 UNITED! STATES HARRY W. BAUMER, OI'OHICAGO,ILLIENOIS PATENT. orrlc a I rnornc'rrvn nnvxcn non ELECTRIC CIRCUITSApplication filed June 13,

This invention relates to improvements in protective devices forelectric circuits, and more particularly to such devices wherein a fuseis used to rupture electric currents of 5 high potentials- The mainobject of the invention is to provide simple and positive means foropening the circuit by forming an air gap in high tension circuits withcertainty and great ra i0 pidity.-

Another object is to produce in such a device, means for holding thefuse in a remove able cartridge which .may be quickly, without the aidof special tools, and

i replaced by another cartridge having a new with specification; theinvention consisting in the devices and combinations of devices hereinillustrated, is described and more particularly pointed out in theappended claims. In that form in which I have chosen toherein'illustrate my invention (it being manifest that other forms maybe used) by means of the accompanying drawings:

Figure 1 is a central, longitudinal sectional view of a device embodyingthe invention, the section being taken in the plane indicated by dottedline l1 on Fig. 3. 1 7 Figures 2 and 3 are transverse, sectional *viewsof the same, the sections being taken in the planes indicated by thedotted lines 2-2 and 3-3 respectively, onFig. 1.

Figure 4 is a view similar to that of Figure 1, partly broken away, toillustrate the pos1 tion of the parts when the fuse is blown.

Figure 5 is a side view of the fuse holding cartridge, detached; and

Figure 6 is a vertical, sectional view showing a modification. i

The form illustrated in these drawings comprises a terminal element uponeach end of anint'ermed-iate insulating housing memremoved 1925. SerialNo. 36,853.

-ber, a conducting element extending longitudinally of and movable partway through the 'housingmember, said movable member being electricallyas well as mechanically connected at one end to one of the terminalelements, a cartridge element removably located in the other end of thehousing and having a fusible element positioned therein and'electricallyconnected to the longitudinally movable element and also to the otherterminal element, and motor means within the removable element adapted,upon thezblowingof the fuse, to operate the longitudinally movableelement and force the latter into such a position as will not only givea .visible indication to the repair man that the fuse has been blown,but also to cause the formation of an air gap sufficient to preventcurrent leakage or other injurious action in the circuitor to apparatusconnected therewith. More specifically now referring to Figures 1, 2 and3, my device, indicated as a whole by the letter A, comprises a housingmember 1 of any suitable shape, but-preferably of the tubular formshown. Thehousing is provided upon its ends with tubular meni bers orferrules 2 and 3 secured thereto in' any suitable manner. The housinglis made of insulating material, as for example, fibre or bakelite. Anyother suitably insulating material may be used. The end members 2 and 3are made of any suitable conductor metalthrough which current will flow.The device A will be installed in an electric circuit, in any suitablemanner, as for example by the familiar spring clip in common use, andtherefore not shown.

Within the housing 1, I secure a centrally apertured disc or partition 4by screws 5 or any other suitable means, thus forming within the housing1, lower and upper chambers 6 and 7 below and above, respectively, saidpartition disc 4. To the lower member 2 is applied a metallic closure orlid 8 movably secured in position in any convenient manner, as, forexample, by a hinge 9 and spring retaining clip 10. e

Resting upon this closure 8, when in the position shown in. Fig. 1,is'the base end 11 of a longitudinally movable conductor rod 12,electrically and mechanically connected to the conductor member 2 by asuitable conductor cable 13. This cable I prefer to make relativelystrongand' not easily breakable, for a purpose hereinafter stated.

This conductor rod 12 extends through the apertured partition 4 andlengthwise of the housing in the upper chamber 7. It is provided uponits upper end l4 with screw threads or other suitable means whereby itmay be quickly connected to and quickly disconnected from the lowermovable member 15 of what I herein choose to designate as a cartridge,and which latter is indicated as a whole by the letter B (see Fig. 5).

The cartridge B-comprises a tubular portion 16 made of any suitableinsulating material, such, for example, as lava, with its upper end 17enlarged to form a supporting, annular shoulder 18. The central bore orspace 21 is contracted at its lower portion, but will be suficientlylarge in cross sectional area to form a'bearing for the member 15.- Atits upper end, the chamber'is provided with an interior, annularshoulder or bear- I ing for an apertured insulating disc 19, and

a metal conductor disc'20. The intermediate portion of the bore orchamber 21 is filled conductor rod 12 extends.

with a quickly ignitible and explosive material, expansible gas or othermotor element,

such, for example, as gun powder, indicated at 22. A fuse wire 23 ispassed through the motor member 22 and is soldered or otherwise unitedat one end to the member 15 and at the other end to the disc 20.

Within the chamber 7 of the housing 1, and above the partition 4 is asuitable smothering or are extinguishing material 24, as, for example,sand, through which the movable Extending upwardly through the material24, with its lower erfd also passing through the partition 4, is ahollow tube 25. The tube 25 is. in open communication at its upper endwith the upper portionof the chamber 7 and at its lower end with thechamber 6. Within the upper part of the housing above the chamber 7 is arelatively thick, tubular reinforcing member 26, made of any suitableinsulating material, as for example lava, provided at its upper end withan interiorly arranged annular shoulder,'upon which the shoulder 18- ofthe head 17 will rest, and whereby the cartridge B is supported.

The member 3 may be secured upon the housing A and to the reinforcingmember 26 by screws 27 in any .suitable manner. A metallic conductor capmember 28 covers the end of the device A, being readily removable bymeans of thumb screws 29, or other suitable means. These screws 29 passinto the upper end of the reinforcing member 26 and serve not only tohold the parts together but alsoto force the cap member 28 into firmshown in Figure 1, is positioned for use in the line fuse clips (notshown) the normal current will pass from one set of clips through member3, cap 28, disc 20, fuse wire 23, end members 15 and 14, rod 12,conductor Wires 13, lower contact 11, and lid 8 to member 2 and theother clips.

When the fuse wire 23 is blown by the presence of excess current, theare produced will instant-1y operate the motor element 22, whichsurrounds the fuse wire in the chamber 21 and the motor element willexert a downward thrust or pressure suihcient to quickly push themembers 15 and 14 and the rod 12 downwardly. This pressure will besufficient to at once overcome the holding tension of the spring 10 andrelease the closure 8. The parts will then assume the positionsindicated in Fig. 4.

It will be observed that in this fuse-blown of a flow of current afterthe fuse is once blown or of trouble which might otherwise occur due toany excess of pressure by the motor element, will be prevented.

- It will be understood that the wire 13 will straighten out when thelid 8 is pushed to the open position, as shown in Fig. 4, and by reasonof the inherent strength of the cable or of the incorporation therewithof a metal chain or other suitablemeans (not shown), there will be alimit to the downward movement of the rod 12, and that it will besupported as shown,by the cable. It will also be understood that thisposition of the parts, as shown in Fig. 4, will afford a visible meansof enabling the repair man or other person to quickly determine theparticular location where the device has interrupted the current by theblowing of the fuse.

To restore the current in the line, the device A is removed from theconnector clips and the cap 28 removed, the old cartridge B is taken outand thrown away, the rod 12 pushed up until the end15 is accessible fordisconnection from the end 14 of the rod, a new cartridge B inserted inthe bore of the reinforcing member 26 and the end 15 of the newcartridge is united with the upper end replaced and the cable 13 foldedin position in the .chamber 6 and the lid 8 closed and locked by thespring 10. The device A is turned circumferential flange 31 to fit,frictionally, over the member 2 and having on its inner face a raisedboss 32 upon which the base end of the rod 12 will-rest when the closureplate 30 is in operative position. The downward movement of the rod 12due to the action of the motor element will quickly push the plate 30from the member 2, thus uncovering the lower chamber 6. The plate 30 maybe held from dropping away too'far by using one of the cable members 13whichfas shown, is connected at oneend 33 to the plate 30 and at itsother end 34 to the member 2.

With the renewable cartridge containing the fusible-element andexplosive compound positioned within the metal sleeve or ferrule 3,-this sleeve serves as an effective shield to prevent corona from formingalong the fusile element and otherwise affect the explosive compound. Ip

It will be apparent that with the plunger 15 embodied as a part of therenewable cartridge element -B and arranged to be detachably secured tothe end 14 of the rod 12, the cartridge is self-containedand may bereadily replaced for the purpose of renewing the fuse. By providing thewasher 19 with a small aperture in which the fuse element 23 fits, thefuse element 'on blowing cannot fire up through the aperture and oxidizethe end disk 20. In operation. unon a blowing of the fuse element, asmalLball of metal usually forms at the lower end of the aperture toprevent such oxidation. This is advantaeous in keeping the permanentparts of the so clean.

It is also'a distinct advantage to have the..

vent opening from the chamber 7 normally closed to the atmosphere so asto prevent the admittance of moisture. This is obtained in the preferredform of the invention by venting the chamber 7 through the tube 25 andalso through the lower chamber 6 when the end closure 8 is open.

. It will be readily understood that while I have described in detail myinvention in the form which I have herein illustrated, my invention isnot limited to the details of construction so described, since,manifestly,

other changes may be made in structural details without departing fromthe spirit of the invention, as set forth in the appended claims. I

I claim as my invention 1. A protective device for electric circuits,comprising a non-conductor housing having a removable conductor memberon one end and a hinged conductor member on the other end, a movableconductor member slidably mounted within the housing and electricallyconnected at one end with the hinged conductor member, a removableextension on the other end ofthe movable conductor, a non-conductor,removable cartridge member interiorly provided with a motor element,

and a fuse connected at one end with said extension member andelectrically connected at its other end with the housing conductormember, so located in the cartridge thatupon being blown its arc'willactuate the motor element. 4 2. A protective device for electriccircuits, embracing a housing provided with conductor means adapted foroperative/connection in circuit, a fuse, a movable conductor member,means for actuating the movable member when the fuse is blown byabnormal current conditions in circuit, and means permit ting the endofthe movable member to project beyond the housing when the fuse is blown,said means including a removable closure lid on which the end (if themovable member, is supported within the housing when the lid is closed.

3. A protective device for electric circuits, embracing a housingprovided with conductor means adapted for operative connection incircuit, a fuse, a movable conductor member, means for actuating themovable memher when the fuse is blown by abnormal current conditionsincircuit, and means permitting the end of the movable member to projectbeyond the housing when the fuse is blown, said means including aremovable closure lid on which the end of the movable member issupported within the housing when the lid is closed, and means forretaining the closure lid secured to the housing when in its removedposition.

4. A protective device for electric circuits, embracing a housingprovided with conductor means adapted for operative connection incircuit, a fuse, a movable conductor member, means for actuating themovable member when the fuse is blown by abnormal current conditions incircuit, a chamber in the housing containing a smothering material, theconductor member extending through and its ends projecting normallyabove and below said material, the end of saidmember connected with thefuse being completely surrounded by said material'when the fuse is blownand said conductor is actuated, and means for establishing atmosphericcommuni'cation with the chamber above the said material. when the fuseis blown, including a conduit passing through said material with itsopen ends located above and below the normal levels of the saidmaterial.

5. A protective device for electric circuits, embracing a housingprovided with conductor meansadapted for operative connection incircuit,a fuse, a movable conductor member, means for actuating the movablememher when the fuse is blown by abnormal cur rent conditions incircuit, a chamber in the housing containing a smothering material, theconductor member extending through and its ends projecting normallyabove and below said material, the end of said member connected with thefuse being completely surrounded by said material when the fuse is blownand said conductor is actuated, and

means for establishing atmospheric communication with the chamber abovethe said material when the fuse is blown, including a wall in thehousing upon which said material is supported, a chamber in the housingbelow the wall, a hinged lid adapted to be opened by the movement. ofthe movable conductor, and a tubular member supported by the wall andextending through the material, its ends being constantly in opencommunication with the upper and lower chambers.

6. A protective device for electric circuits comprising a tubularhousing of nonconducting material, a wall therein forming an upper and alower chamber in said housing, a conductor member onone end of thehousing a lid on the housing for closing the lower chamber, a conductor,closure member removably" mounted on the other end of the housing, anon-conductor cartridge member removably mounted in the upper part ofthe upper chamber in the housing, a chamber for a motor element withinsaid cartridge, a conductor member slidably mounted in the wall with itslower end extending into the lower chamber and resting upon the closurelid, a conductorcable connecting thelower end of said slidable conductorwith the housing conductor member with which the lid is in electricalcontact, a removable extension on the.

upper end of the slidable conductor, slidably supported by the cartridgeand projecting into the explosive chamber therein, a fuse I secured atone end to said extension member,

- passing through the motor chamber and 1,7sajoso conductor members oneach end of the housing adapted for operative connection in an electriccircuit, a movable conductor operatively connected within the housingwith one of the end conductors, a fusible member stationarily mountedwithin the housing and connected with the other end conductor and withthe movable conductor, and means surrounding the fusible member ignitedby the abnormal current changes which blow the fuse and which meansactuate the movable conductor.

8. A protective device for electric circuits havinga housing providedwith conductor .means adapted for operative connection in circuit, aremovable cartridge member normally within the housing and whichembraces a fuse and an explosive element adapted to be ignited when thefuse is blown by abn0r mal current conditions, a movable conductormember adapted. to be actuated upon the ignition of the explosiveelement, and means for exposing to view the end of the movable memberwhen the fuse is blown.

9. A protective device for electric circuits having a housing providedwith conductor means adapted for operative connection in circuit, a fusestationarily mounted within the housing adapted to be ruptured byabnormal current changes, a movable conductor forming a piston, meansforming a cylinder for said piston and enclosing said fuse so that thepiston will be actuated upon the blowing of the fuse, and means forrelieving the pressure of the motor means.

10. A protective device for. electric circuits having a housing providedwith conductor means adapted for operative connec- 7 tion in circuit, afuse within the housing, a movable conductor normally attached to thefuse, motor means operable by the arc of the blown fuse for actuatingthe movable conductdr when the fuse is blown by abnormal currentconditions in circuit, and a housing chamber containing a smotheringmaterial, the movable conductor being within sald chamber and having itsends extending above and below said smothering material and adapted tomove so that its fuse connected end will becompletely surrounded by thematerial upon the blowing of the fuse.

11. A protective device for electric circuits having a housing providedwith conductor means adapted for operative connection in circuit, a fusewithin the housing, a movable conductor member normally attached to thefuse, motor means for actuating the movable conductor when the fuse isblown by abnormal current conditions in circuit, a housing chamber,smothering material in said chamber, a, movable conductor extendingthrough, and its ends projecting normally above and below, saidmaterial, and means for establlshing atmospheric communlcation with thechamber above said material when the fuse is blown.

12. A renewable fuse comprising, in combination, an insulating tubehaving metallic ferrules secured to and surrounding said tube adjacentits ends, areinforcing sleeve of insulating material within one ferrule,and a renewable cartridge element positioned in said sleeve, saidelement containing a fuse connected at one end to said ferrule.

12-3. A renewable fuse comprising, in combination, an insulating tubehaving a metallic sleeve secured to and surrounding a portion of saidtube and a renewable cartridge element positioned in said casing withinsaid sleeve. said element containing a fuse, one end of which isconnected to the sleeve, and an explosive element surrounding a portionof said fuse.

14. Afuse comprising, in combination, a tubular casing, end-closures forthe opposite ends of said casing, a sand compartment disposedintermediate the ends of said casing, and means arranged to vent saidcompartment through the lower end of the fuse when that end closure isremoved.

15. A renewable cartridge forfuses of th I character describedcomprising, in combination, a tubular casing of insulating material, aplunger slidably mounted in one nd of said casing, a closurefor theopposite end of the casing. a fusible element secured at one end to saidplunger, means to secure the other end of said element to'said closureand a washer adjacent said closure and having an aperture through whichsaid element passes.

16. A fuse comprising, in combination, a tubular casing, metallicferrules secured to the opposite ends thereof, a compartmentintermediate the ends of said fuse arranged to receive are extinguishingmaterial, a rod normally extending into said compartment and I connectedpermanently to one ferrule, and a renewable cartridge element positionedwith- 1 and means secured to said member and to said casing to limit theoutward movement of said member.

18 A fuse adapted normally to be mounted in an upright positioncomprising a tubular casing of insulating material, ferrules at theopposite ends thereof, means toclose the upper end arranged to preventthe entrance of foreign matter into the casing, a chamber witl 1 thecasing intermediate its ends for receiving an arc extinguishing sub--stance, a vent passage for said chamber including a. vent tube extendingupwardly therein, and means arranged normally to close the vent passageadapted upon a blowing of the fuse to open said passage.

19. A fuse adapted normally to be'mounted in an upright positioncomprising a tubular casing of insulating material, ferrules at-theopposite ends thereof, means to close the upper end arranged to preventthe entrance of foreign matter into the casing, a renewable cartridgeelement positioned. in the upper end of said casing adjacent saidclosure, a chamber within the casing intermediate its ends, a vent tubeextending upwardly in said chamber, and means arranged normally to closethe vent passage adapted upon a blowing of the fuse to open saidpassage.

20. In a renewable-high tension cartridge fuse, the combination of aninsulating tube, a fusible element positioned centrally of said tube, anionizablesubstance surrounding said element, and a metallic memberspaced outwardly from and. completely encircling said substance.

In testimony that I claim the foregoing as my invention I afiix mysignature this 11th day of June, 1925.

HARRY W. BAUMER.

